I don't have any pictures of my work bench but I made a drawing of it.
The legs are 4x4 cut to height.
The tan parts are 2x4 cut to length
The table top is a sheet of 3/4" plywood ripped and stacked with the factory edge on the outside for a good sturdy 1 1/2" thick base to attatch tempered masonite to.
The green is the masonite placed smooth side up. It can be glued with contact cement or screwed in place.
The light blue is a sheet of pegboard for hanging tools above and heavy bulky items below like your press or powder dumper.
Of course there are numerous bolts and nuts and washers.
The crossed 2x4 must be relieved so they lap each other at the center where they cross.

The drawing has been shortened in proportion so it all fits on one screen. Dimensions have been ommitted because you should make it the size you want.

Hope this helps. It is plenty heavy and I have never had it tip on me while full length sizing. But as always use your own discretion.

GHA - You definately need more room!
I use a black and decker workmate as a bench which works ok but I have to be very organized and work slowly due to the space constraints. I use this for now because I have not set up my reloading room in my new house and probably will wait till the kids are gone (soon).